A company who carries out one project may place orders with a plurality of contractors and/or suppliers for tasks of the project so that the project is shared among them. To manage the progress of the tasks assigned to the contractors, staffers in the company typically create a basic schedule for the project and present it to the contractors, for example by facsimile or postal mail. The contractors may modify the basic schedule as they believe appropriate and send the modified schedule back to the staffers.
After the project starts, the staffers in the company may inquire each of the contractors about progress. The inquiry is typically made by telephone, e-mail, or other means. The staffers record the obtained progress data in the schedule to check whether the schedule has been met.
According to the above-described method, it may be difficult to adjust a schedule between the company and the contractors, because the communication between them is carried out by facsimile, postal mail or e-mail. When the staffers make a modification to the schedule, the contractors may be unable to view the modified schedule in real time. Therefore, progress may be behind the schedule. Furthermore, collecting progress data from a plurality of correctors by telephone or e-mail is a heavy load. In particular, if a large amount of work is to be carried out by a plurality of contractors, it may be difficult to collect progress data and record it in a schedule quickly and accurately.
Japanese Patent Application Laid-Open No. 5-6378 describes a system for managing the schedule for work conducted by a plurality of members. Workstations of members are connected via a network. The workstation of each member includes a personal schedule management part. A coordinated schedule management part provided in a server manages the overall schedule of the work based on the personal schedule data obtained from each personal schedule management part. According to the system, collecting personal schedule data imposes a heavy load on the coordinated schedule management part.
Japanese Patent Application Laid-Open No. 11-31179 describes a method for managing the progress of a transaction. The method involves obtaining transaction data transferred through a network and creating a schedule based on the obtained transaction data, the schedule being represented by process stages and completion dates defined for a plurality of companies. When progress data is obtained, it is recorded in the schedule. If an actual completion date is behind the schedule, completion dates defined for the subsequent process stages are modified accordingly. According to the method, a managed party can not check on the schedule in real time. Therefore, it is difficult to adjust the schedule between the managing party and the managed party.
On the other hand, a typical schedule display format is a table in which the horizontal axis represents date and the vertical axis represents schedule items. When a schedule is created, a due date for each item is recorded in the table. When progress data is obtained, an actual completion date for each item is recorded in the table. The progress of work is managed item by item through the comparison of the due date and the actual completion date.
Japanese Patent Application Laid-Open No. 9-174392 discloses a system for generating a progress chart. Progress points indicating progress rates are plotted on a schedule line and progress check dates are plotted on a calendar line. A progress line is drawn connecting each progress check date and corresponding progress point. The progress chart visually shows the progress of work in which multiple tasks are carried out concurrently.
Japanese Patent Application Laid-Open No. 8-305749 describes an apparatus for creating a work plan based on a standard timetable pattern. The standard timetable pattern represents a correspondence between a standard timetable and standard man-hours for each work category. The apparatus displays the work plan and obtained progress data for each category in tabular form, the work plan and progress data being expressed in man-hours.
Japanese Patent Application Laid-Open No. 11-232323 describes a method for keeping track of the state of each room at a facility. According to the method, data relating to various events that have taken place at each room is displayed. For example, when a room is being cleaned, an indicator for the cleaning event is displayed. Thus, it is determined whether work as to each room is done in a proper manner.
According to the above-described display formats, it may be difficult to grasp at a glance which of items needs to be handled. Also, it may be difficult to identify a relationship among tasks. In particular, when a project comprises a plurality of tasks, it may be difficult to determine whether the progress for each task is behind or ahead of the schedule.